I remember an argument onboard a KLMuk 146 several years ago. We were within minutes of closing the doors at Amsterdam. One connecting passenger didn't realise that due to the "change of gauge" the size of bag he'd been allowed to take into the cabin on his flight into AMS earlier (on KLM) was too big for the 146. The flight attendant insisted that he give it to her so that it could be put in the hold. He was quite upset about this.